Pressure-sensitive adhesive tape

Abstract

This invention provides a PSA tape that comprises a PVC film comprising a plasticizer, and a PSA layer placed at least on one face of the PVC film The PSA tape yields a condensation amount of 5 mg or less in a condensation amount measurement carried out by storing a piece of the PSA tape having a surface area equivalent to a circle of 80 mm diameter at 120° C. for 16 hours.

The invention claimed is: 
     
       1. A pressure-sensitive adhesive tape comprising
 a polyvinyl chloride film comprising a plasticizer, and 
 a pressure-sensitive adhesive layer placed at least on one face of the polyvinyl chloride film, 
 wherein the plasticizer is a polyester-based plasticizer having a weight average molecular weight of 1000 or greater and a carboxylic acid ester having a weight average molecular weight of less than 1000, 
 the amount of the carboxylic acid ester having the molecular weight of less than 1000 contained in the polyvinyl chloride film is 1 part by weight or greater and 30 parts by weight or less relative to 100 parts by weight of polyvinyl chloride, 
 wherein the polyester-based plasticizer having the weight average molecular weight of 1000 or greater of the polyvinyl chloride film satisfies the formula:
   1≤( W   PLH   /W   PLL )≤15,
 
 
 wherein W PLH  is the amount by weight of the polyester-based plasticizer having the weight average molecular weight of 1000 or greater contained in the polyvinyl chloride film, and wherein W PLL  is the amount by weight of the carboxylic acid ester having the weight average molecular weight of less than 1000 contained in the polyvinyl chloride film, and 
 with the pressure-sensitive adhesive tape yielding a condensation amount of 5 mg or less in a condensation amount measurement carried out by storing a piece of the pressure-sensitive adhesive tape having a surface area equivalent to a circle of 80 mm diameter at 120° C. for 16 hours. 
 
     
     
       2. The pressure-sensitive adhesive tape according to  claim 1 , wherein the plasticizer content in the polyvinyl chloride film is 10% by weight or greater, but 50% by weight or less. 
     
     
       3. The pressure-sensitive adhesive tape according to  claim 1 , wherein the polyvinyl chloride film comprises an aliphatic acid metal salt. 
     
     
       4. The pressure-sensitive adhesive tape according to  claim 3 , wherein the aliphatic acid metal salt comprises at least one metal species that belongs to any one of groups 1, 2, 12, 13 and 14 (but excluding Pb) of the periodic table. 
     
     
       5. The pressure-sensitive adhesive tape according to  claim 3 , wherein the aliphatic acid metal salt comprises at least one metal species selected from a group consisting of Li, Na, Ca, Mg, Zn, Ba and Sn. 
     
     
       6. The pressure-sensitive adhesive tape according to  claim 3 , wherein the aliphatic acid metal salt is a metal stearate, metal laurate, or a combination of a metal stearate and a metal laurate. 
     
     
       7. The pressure-sensitive adhesive tape according to  claim 1 , wherein the carboxylic acid ester having the weight average molecular weight of less than 1000 comprises an ester of a carboxylic acid and an alkyl alcohol with 6 to 14 carbon atoms. 
     
     
       8. The pressure-sensitive adhesive tape according to  claim 1 , wherein the carboxylic acid ester having the weight average molecular weight of less than 1000 comprises at least either a trimellitic acid ester or a pyromellitic acid ester. 
     
     
       9. The pressure-sensitive adhesive tape according to  claim 1 , wherein the polyester-based plasticizer having the weight average molecular weight of 1000 or greater comprises an adipic acid-based polyester plasticizer having a weight average molecular weight of 3000 or greater, but 7000 or less. 
     
     
       10. The pressure-sensitive adhesive tape according to  claim 1 , wherein the amount of the carboxylic acid ester having the weight average molecular weight of less than 1000 contained in the polyvinyl chloride film is 1 part by weight or greater, but 10 parts by weight or less relative to 100 parts by weight of polyvinyl chloride. 
     
     
       11. The pressure-sensitive adhesive tape according to  claim 1 , wherein the polyvinyl chloride film comprises an antioxidant. 
     
     
       12. The pressure-sensitive adhesive tape according to  claim 1 , wherein the polyvinyl chloride film comprises an elastomer. 
     
     
       13. The pressure-sensitive adhesive tape according to  claim 1 , wherein the pressure-sensitive adhesive layer comprises a rubber-based polymer and a tackifier resin, wherein the tackifier resin content is 50 parts by weight or greater, but 150 parts by weight or less relative to 100 parts by weight of the rubber-based polymer. 
     
     
       14. The pressure-sensitive adhesive tape according to  claim 13 , wherein the pressure-sensitive adhesive layer comprises one, two or more species of tackifier resin selected among rosin-based resins, petroleum resins, terpene-based resins, phenolic resins, coumarone-indene-based resins and ketone resins. 
     
     
       15. The pressure-sensitive adhesive tape according to  claim 14 , wherein the pressure-sensitive adhesive layer is a rubber-based pressure-sensitive adhesive layer comprising a rubber-based pressure-sensitive adhesive as the primary component. 
     
     
       16. A wire harness comprising electric wires and the pressure-sensitive adhesive tape according to  claim 1  wrapped around the electric wires. 
     
     
       17. A pressure-sensitive adhesive tape comprising
 a polyvinyl chloride film comprising a plasticizer, and 
 a pressure-sensitive adhesive layer placed at least on one face of the polyvinyl chloride film, wherein 
 the plasticizer content in the polyvinyl chloride film is 10% by weight or greater, but 50% by weight or less, 
 the polyvinyl chloride film comprises, as the plasticizer, a polyester-based plasticizer having a weight average molecular weight of 1000 or greater and a carboxylic acid ester having a weight average molecular weight of less than 1000, 
 the carboxylic acid ester having the weight average molecular weight of less than 1000 comprises at least either a trimellitic acid ester or a pyromellitic acid ester, 
 the polyester-based plasticizer having the weight average molecular weight of 1000 or greater comprises an adipic acid-based polyester plasticizer having a weight average molecular weight of 3000 or greater, but 7000 or less, 
 the amount of the carboxylic acid ester having the weight average molecular weight of less than 1000 contained in the polyvinyl chloride film is 1 part by weight or greater and 30 parts by weight or less relative to 100 parts by weight of polyvinyl chloride, 
 the pressure-sensitive adhesive layer comprises a rubber-based polymer and a tackifier resin, wherein the tackifier resin content is 50 parts by weight or greater, but 150 parts by weight or less relative to 100 parts by weight of the rubber-based polymer, and 
 wherein the polyester-based plasticizer having the weight average molecular weight of 1000 or greater of the polyvinyl chloride film satisfies the formula:
   1≤( W   PLH   /W   PLL )≤15,
 
 
 wherein W PLH  is the amount by weight of the polyester-based plasticizer having the weight average molecular weight of 1000 or greater contained in the polyvinyl chloride film, and wherein W PLL  is the amount by weight of the carboxylic acid ester having the weight average molecular weight of less than 1000 contained in the polyvinyl chloride film.